Sleep disorders and vascular responsiveness in patients with rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis (RA) is the most common systemic autoimmune disease characterized by chronic systemic inflammation. Half of the deaths of patients with RA are due to cardiovascular diseases (CVD), considered to be 1.5 to -2.0-fold that in the general population. Patients with RA also experience poor sleep, which by itself is associated with endothelial dysfunction, CVD events and sudden death. Our aim was to study the mechanistic pathways and the correlations between sleep efficiency and vascular reactivity of patients with RA. METHODS AND RESULTS: A prospective study that evaluated quality of sleep using ACTi Graphs, vascular inflammation and endothelial function of 18 patients with RA. Inflammation was studied by levels of E-selectin, intercellular adhesion molecule 1 (ICAM-1) and NO in serum. Endothelial function was studied using the brachial artery plethysmography method. Eighteen RA patients (aged 57.56 ± 13.55 years; 16 women) with a long-standing active RA: Eight patients had impaired sleep efficiency and 10 had a good sleep efficiency. Those who had an impaired sleep had larger baseline diameters of the brachial artery (0.39 ± 0.08 cm vs. 0.32 ± 0.04 cm; P = 0.02). Negative correlations were found between baseline brachial artery diameter and sleep efficiency (P = 0.01), and with NO level (P = 0.04). Stepwise regression found that brachial artery diameter at baseline and NO level could predict sleep efficiency (r2  = 0.543, P = 0.01). CONCLUSION: Vascular reactivity could predict quality of sleep in patients with RA. Quality of sleep may serve as an independent CVD risk factor in patients with RA.

Eating attitudes in a diverse sample of Israeli adolescent females: a comparison study.

OBJECTIVES: To estimate the eating attitudes in Israeli Jewish female adolescents. METHODS: A representative sample of 1270 females in grades 7-12 from five different Israeli schools from five different residential areas were assessed by EAT-26. RESULTS: Of the total sample, 19.5% were identified as having abnormal eating attitudes. In terms of age, the 16 year olds were found to have the significantly highest rate of total and positive EAT-26 scores. As for school subgroups, the secular boarding schools had the significantly highest rate and the kibbutz had the lowest rate of positive EAT-26 scores for the total and for all subscales. DISCUSSION: EAT-26 was found to be a useful tool for screening and identifying at-risk groups in a large adolescent Israeli population.

Long-term sleep disturbances in adolescents after minor head injury.

It has been demonstrated that patients in the acute phase after minor head injury (MHI) complain of sleep disturbances. The purpose of the present study was to characterize the long-term effects of MHI on sleep in adolescents. Nineteen adolescents who had suffered MHI 3 years before the study and had complained of sleep disturbances completed a sleep questionnaire and were investigated in the sleep laboratory by whole-night polysomnographic recordings and were actigraphically monitored for 5 days at home. Questionnaire results revealed severe complaints regarding sleep behavior. Polysomnographic recordings revealed that in comparison with controls, MHI was associated with lower sleep efficiency (79.8 +/- [9.8]% vs 87.7 +/- [6.8]%; P < 0.005), with more wake time (10.6 +/- [9.0]% vs 3.4 +/- [4.4]%; P < 0.005), and with more awakenings lasting more than 3 minutes (2.1 +/- [1.5] vs 0.6 +/- [0.8]; P < 0.005). These findings were confirmed by actigraphic monitoring that revealed lower sleep efficiency (90 +/- [5]% vs 94 +/- [3]%; P < 0.05), more minutes of wake time (49 +/- [21] min vs 28 +/- [15] min; P < 0.05), and a trend toward more awakenings longer than 5 minutes (1.8 +/- [0.8] vs 1.2 +/- [0.8]; P = 0.063). Our data demonstrated that 3 years after MHI without any discernible clinical sequel, adolescents still complain of sleep disturbances that could be confirmed by both polysomnographic and actigraphic monitoring.

Daily and yearly burnout symptoms in Israeli shift work residents.

Burnout is a syndrome of physical and emotional exhaustion that develops among individuals who are open to public demands. In view of their heavy work load and sleep deprivation, we decided to evaluate the impact of long working hours on burnout and psychological status among a sample of residents during the first 2 years of their residency. Seventy-eight residents participated in the study, all residents completed self-administered questionnaires, and their sleep-wake cycle was monitored by a wrist-worn actigraph for a period of 5-7 days. The questionnaires included a short form suitable for Experience Sampling Method (ESM), and a longer background Questionnaire. The results revealed that sleep duration, Work Load and the interaction between them, explain the Negative Mood the day after the night shift. However, positive mood, and fatigue were not affected by sleep duration or workload. In general, after one year of residency, residents become more stressed, less involved in the job, and had a high level of burnout and psychosomatic symptoms. However, after the second year, the burnout symptoms were almost the same as at the beginning except for the level of stress that remained high. Sleep duration was unrelated to the burnout symptoms.

Can we consider medical residents as shift workers?

Although medical residents are characterized by long working hours, night shifts and high levels of work load, it is unclear if their work schedule can be classified as shift work, or if it has a similar impact on residents' well-being. The present paper compared the profile of complaints about sleep or daytime functioning of medical residents to that of rotating shift workers and day workers, of similar ages. Sixty-one residents (aged: 32.2 +/- 2.2 years), after 2 years of residency, participated in the study. The two control groups with a similar age range (26-40 years) were chosen, and included 94 rotating shift workers and 146 day workers. All subjects completed self-administered questionnaires on their sleep habits, and their sleep-wake cycle was monitored by a wrist-worn actigraph. Ten percent of the residents complained about difficulties falling asleep, 34% complained about morning tiredness, 14% complained about mid-sleep awakening, and 20% about prolonged fatigue. The residents slept significantly less than the day workers, and their sleep efficiency was significantly higher. When examining their subjective complaints profile, residents complained more than day workers and their answers were more similar to those of rotating shift workers, therefore they can be considered to be characterized as shift workers.

Sleep-wake monitoring in women suffering from anorexia nervosa.

There is evidence that some Anorexia Nervosa (AN) patients have sleep abnormalities. No studies of their sleep-wake cycles in a natural environment have yet been reported. The purpose of this study was to evaluate an objective and subjective sleep-wake cycle of AN patients compared to a healthy age-equated control group (CON). Twenty-one AN female and sixteen CON female subjects were recruited. Sleep-wake patterns were monitored using ambulatory monitoring mini-actigraphs for one week. Each subject completed self-report questionnaires. The self-report questionnaires revealed significantly more sleep disturbances in AN than CON, whereas the ambulatory sleep data revealed no significant differences between the two groups in sleep-wake cycle.

Actigraphic monitoring (actigraphy) of circadian locomotor activity in schizophrenic patients with acute neuroleptic-induced akathisia.

BACKGROUND: Actigraphy is a quantitative method for measurement of motor activity. In the present study we used actigraphy to examine diurnal variations in locomotor activity of schizophrenic patients with neuroleptic-induced akathisia (NIA). METHOD: Thirty-two schizophrenic patients, 16 with NIA and 16 without (DSM-IV criteria) underwent 24-h actigraphic monitoring. Clinical assessments of NIA were conducted with Barnes Akathisia Scale (BAS) at 08:00, 12:00, 16:00 and 20:00. Sleep parameters (duration, latency, continuity and efficacy) were assessed by actigraphy. Sleep quality was evaluated by a self-rated sleep questionnaire. RESULTS: NIA patients demonstrated persistent higher daytime motor activity from 11:30 to 14:15 and from 18:00 to 21:00 than controls. There were no differences between the groups in nighttime motor activity, confirming clinical observations that NIA tends to disappear during sleep. Subject's sleep assessments were similar in the two groups. CONCLUSIONS: Actigraphy seems to be a reliable, non-invasive, method of measuring motor activity in patients with NIA. Its sensitivity and specificity as an objective quantitative diagnostic instrument in patients with NIA merits further investigation.

Sleep-wake cycles in women with binge eating disorder.

OBJECTIVE: Binge eating disorder (BED) is a new diagnostic category in the 4th ed. of the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV). The majority of studies on sleep characteristics in overweight women have used nonbinging obese women. The aim of this study was to evaluate sleep characteristics in obese BED patients in comparison to non-BED obese (OB) and nonbinging normal weight (NW) women. METHOD: Eighteen females with BED, 13 OB, and 16 NW women were recruited. Sleep-wake patterns were monitored for 1 week using mini-actigraphs and self-report questionnaires. RESULTS: Their ambulatory sleep data revealed that BED and OB subjects had significantly lower sleep efficiency, had more wake during sleep, and had less zero activity than the NW group. The self-report questionnaires presented significantly more sleep disturbances in the BED and OB groups than in the NW group. DISCUSSION: The objective results support the subjective sleep disturbances reported by the two obese groups, the BED and the OB. A possible explanation for these findings could be weight-related physical discomfort or the existence of breathing disorders in sleep. Further research, for example, overnight polysomnography recordings and follow-up treatment, is required.

Naturalistic sleep monitoring in women suffering from bulimia nervosa.

OBJECTIVE: Eating disorders may be associated with alterations in sleep. There is evidence that some bulimia nervosa (BN) patients have sleep abnormalities. No studies of their sleep-wake cycles in a natural environment have as yet been reported. The purpose of this study was to evaluate an objective and subjective sleep-wake cycle of BN compared to a healthy age-equated control group (CON). METHOD: Twenty-nine BN female and eighteen CON subjects were recruited. Sleep-wake patterns were monitored using ambulatory monitoring, mini-actigraphs (Min-Act), for 1 week. Each subject completed self-report questionnaires. RESULTS: The self-reporting questionnaires revealed that BN complained of significantly more sleep disturbances than CON. The ambulatory sleep data revealed significant differences between BN and CON in sleep onset and offset time. DISCUSSION: BN had sleep onset and sleep offset of 1 hr later, which may be connected to binge-purge patterns during the day. It is suggested that future research should focus on BN after remission.

Estimating sleep patterns with activity monitoring in children and adolescents: how many nights are necessary for reliable measures?

STUDY OBJECTIVES: This study provides estimates of reliability for aggregated values from 1 to 7 recording nights for five commonly used actigraphic measures of sleep patterns, reliability as a function of night type (weeknight or weekend night), and stability of measures over several months. DESIGN AND SETTING: Data are from three studies that obtained 7 nights of actigraph data (using Mini Motionlogger actigraphs and associated validated algorithms [ASA]) on children and adolescents living at home on self-selected sleep-wake schedules. PARTICIPANTS: Participants were 169 children aged 12-60 months, and 55 adolescents aged 11-16 years. MEASUREMENTS AND RESULTS: Up to 28% of weekly recordings may be unacceptable for analysis in young participants because of illness, technical problems, and participant noncompliance; studies aiming to collect 5 nights of actigraph data should record for at least 1 full week. Reliability estimates for values aggregated over any 5 nights were adequate (> or = .70) for sleep start time, wake minutes, and sleep efficiency. Measures of sleep minutes and sleep period were less reliable and may require 7 or more nights for estimates of stable individual differences. Reliability for 1- or 2-night aggregates were poor for all measures. We found significant and high correlations between summer and fall session measures for all five variables when weekend nights were included. CONCLUSIONS: Five or more nights of usable recordings are required to obtain reliable actigraph measures of sleep for children and adolescents.

Adolescent sleep patterns, circadian timing, and sleepiness at a transition to early school days.

STUDY OBJECTIVES: This study examined effects on adolescent sleep patterns, sleepiness, and circadian phase of a school transition requiring an earlier start. DESIGN AND SETTING: Adolescents were evaluated in 9th and 10th grades; school start time in 9th grade was 0825 and in 10th grade was 0720. Assessments at each point included 2 weeks of actigraphy and sleep diaries at home, followed by a 22-hour laboratory evaluation, including evening saliva samples every 30 minutes in dim light for determination of dim-light salivary melatonin onset phase (DLSMO), overnight sleep monitoring, and multiple sleep latency test (MSLT). PARTICIPANTS: Twenty-five females and 15 males, ages 14 to 16.2 were enrolled; 32 completed the study in 9th grade and 26 completed in 10th grade. INTERVENTIONS: Participants kept their own schedules, except that laboratory nights were scheduled based upon school-night sleep patterns. MEASUREMENTS AND RESULTS: According to actigraphy, students woke earlier on school days in 10th than in 9th grade, but they did not go to sleep earlier and they slept less. DLSMO phase was later in 10th grade (mean = 2102) than 9th grade (mean = 2024). Sleep latency on MSLT overall was shorter in 10th (mean = 8.5 minutes) than in 9th (mean = 11.4 minutes), particularly on the first test of the morning at 0830 (5.1 vs 10.9 minutes). Two REM episodes on MSLT occurred in 16% of participants in 10th grade; one REM episode occurred in 48%. When those with REM sleep on one or both morning MSLTs (n = 11) were compared to those without morning REM, significant differences included shorter sleep latency on the first test, less slow wave sleep the night before, and later DLSMO phase in those who had morning REM. CONCLUSIONS: Early start time was associated with significant sleep deprivation and daytime sleepiness. The occurrence of REM sleep on MSLT indicates that clinicians should exercise caution in interpreting MSLT REM sleep in adolescents evaluated on their "usual" schedules. Psychosocial influences and changes in bioregulatory systems controlling sleep may limit teenagers' capacities to make adequate adjustments to an early school schedule.

The effects of evening bright light on next-day sleep propensity.

The present study investigated the effects of evening bright light (BL) compared to dim light (DL) on next-day sleep propensity as well as the acrophase of oral temperature and mood scores. A total of 12 male subjects (mean age 23.5 +/- 2.6 years) were exposed to 2 h of evening DL or BL 30 min after sunset for 5 consecutive days. The experimental period started after the 5th day of exposure. After light exposure, subjects remained awake in the sleep laboratory until 07:00 h, when they began the 7/13 ultrashort sleep-wake paradigm, which continued for 24 h until 07:00 h the next day. Oral temperature was measured hourly. The results showed that evening exposure to BL, in comparison to DL, significantly delayed the next-day sleep gate as well as the acrophase of the oral temperature curve and the acrophase of negative mood. The effects of BL on the next-day distribution of sleep stages showed an increase of Stage 2 and less REM (rapid eye movement) during the morning. The results indicate that sleep propensity is regulated by a circadian pacemaker that is responsive to evening BL exposure.

Changing from communal to familial sleep arrangement in the Kibbutz: effects on sleep quality.

Sleep was actigraphically investigated in 27 Kibbutz children while sleeping in communal sleeping houses, and 1 year after changing to familial sleeping arrangements. Three independent control groups of city-living children were also recorded. Two of them were age-comparable, and the third control group was included in order to examine possible effects of the Gulf War on the communal sleep group. The results showed that the sleep quality of Kibbutz children improved significantly after moving to familial sleep. Comparison with the data from the two control groups revealed a greater resemblance between sleep of the Kibbutz children after moving to live with their families and that of the city-living children. Comparing the sleep of the children in communal sleep to that of the additional group of children examined during the Gulf War strengthened the above results, i.e. the communal sleep group that was investigated before the war slept worse than the control children that were investigated during the war. After discarding developmental and physical condition-related changes, it was concluded that the improvement in sleep quality was due to the children's increased sense of security when sleeping with their families.

Melatonin possesses time-dependent hypnotic effects.

The present study investigated the hypnotic effects of 5 mg melatonin in comparison with placebo when administered at 1200, 1700, 1900 and 2100 hours. Eighteen young adults were studied with the 7/13 ultrashort sleep-wake paradigm after an overnight sleep deprivation. Melatonin was administered according to a double-blind Latin square design. After each administration, melatonin significantly increased sleep propensity, the spectral power in the theta, delta and spindles bands, and subjective sleepiness. It significantly decreased the power in the alpha and beta bands and oral temperature. The latency to maximum effect varied linearly from 3 hours 40 minutes at 1200 hours to 1 hour at 2100 hours. These findings indicate that melatonin possesses a time-dependent hypnotic effect and suggest that endogenous melatonin may participate in sleep-wake regulation.

Actigraphic home-monitoring of the sleep patterns of in vitro fertilization children and their matched controls.

The sleep patterns of 35 in vitro fertilization (IVF) children aged 19 to 57 months and their matched controls were evaluated by actigraphic home-monitoring for three consecutive nights. Actigraphic data were analysed by an automated scoring procedure developed in the authors' laboratory. There were no significant differences in activity levels between IVF multiple-birth subjects and their matched controls or between IVF singletons and their matched controls. In contrast, multiple-birth subjects had higher activity levels during sleep and lower sleep efficiency than singletons in both IVF and control groups. Sleep measures showed night-to-night stability in all groups.

Sleep patterns of children sleeping in residential care, in kibbutz dormitories and at home--a comparative study.

The present study compares sleep patterns of two groups of children sleeping away from their families, in residential care (n = 31, age 3.7 +/- 1.7 years) and kibbutz (n = 29, age 3.7 +/- 1.8 years) dormitories, with age-matched children sleeping at home (n = 21, age 3.7 +/- 1.8 years). Sleep was monitored by wrist-worn actigraphs for three consecutive nights and assessed by sleep questionnaires, which were completed by parents of the kibbutz children and caretakers at residential care. Children in the residential care settled to sleep significantly earlier and slept longer than those children living in a kibbutz or at home. The longest period of uninterrupted sleep was more extended for children sleeping at home, compared to those sleeping in communal dormitories. Correlation analysis between various assessments of sleep and waking behaviors revealed a different pattern for kibbutz and residential care children. For the kibbutz children, there were significant correlations between difficulties falling asleep and various attributes of daytime tiredness. Conversely, in the residential care, difficulties falling asleep were significantly and positively correlated with parameters associated with daytime alertness. This pattern of correlations and the actigraphic data indicate that difficulties in falling asleep for children in residential care are probably a consequence of being put to bed too early and according to a rigid schedule, and not the result of emotional factors.

Children's sleep under the threat of attack by ballistic missiles.

The present paper reports on the influence of the Scud missile attacks during the Gulf War on the sleep of Israeli children. Two studies were performed. In the first, sleep habits and sleep disturbances of 61 (mean age 20 months) infants were assessed by questionnaires completed by their parents 5 months before the war and immediately after the end of the War. Comparison of pre- and post-war data revealed no major changes in sleep habits or in sleep quality. In the second study, sleep of 55 children was monitored at home by actigraphs during the last month of the War. All children were aroused during missile attacks, but returned to sleep immediately, with no evidence of carry-over effects once the 'all clear' sign was given. Comparison of sleep quality measures obtained during the War with those of age- and sex-matched children monitored a year before the war did not reveal any significant differences apart from the immediate response to the attack.

The association between the nocturnal sleep gate and nocturnal onset of urinary 6-sulfatoxymelatonin.

The present study investigated the relationship between the time of nocturnal onset of urinary 6-sulfatoxymelatonin (aMT6s) secretion, and the timing of the steepest increase in nocturnal sleepiness ("sleep gate"), as determined by an ultrashort sleep-wake cycle test (7 min sleep, 13 min wake). Twenty-nine men (mean age 23.8 +/- 2.7 years) participated. The ultrashort sleep-wake paradigm started at 0700 hr after a night of sleep deprivation and continued for 24 hr until 0700 hr the next day. Electrophysiological recordings were carried out during the 7-min sleep trials, which were then scored conventionally for sleep stages. Urinary aMT6s was measured every 2 hr. The results showed that the timing of the sleep gate was significantly correlated with the onset of aMT6s secretion. These results are discussed in light of the possible role of melatonin in sleep-wake regulation.

Sleep-wake cycle in shift workers on a "clockwise" and "counter-clockwise" rotation system.

The present study investigated the effects of a 5-day rotating work schedule in the advance, or "counter-clockwise", vs. delay, or "clockwise" direction, on subjective and objective measures of sleep-wake cycles. Twenty-two workers (mean age 27.5 +/- 4.6 years) were studied in the counter-clockwise direction, and 11 workers (mean age 29.83 +/- 5.93) were studied in the clockwise direction. Each worker was studied for a complete rotation cycle (20 days). Sleep-wake cycles were measured by wrist-worn actigraphs in 1-min bins. The clockwise direction was associated with significantly earlier sleep times during the night shift, and with a better synchronization of workers' sleep-wake cycles during night and evening shifts. The present results provide support to the claim that rotating shiftworkers can better adapt to clockwise than counter-clockwise rotations.